Although I have been successful as a spine surgeon in an academic environment, building a respected clinical practice and completing spine biomechanics research for competitively funded projects, I realize that clinical research most directly addresses my motivation for choosing an academic career, and that high-quality clinical research is complex, requiring a long-term commitment and specialized skills. I am in an excellent environment to develop these skills, with supportive colleagues and a supportive chairman. I have developed a five-year training schedule, with the first three years devoted to obtaining an MPH degree. A team of three outstanding individuals has committed to working with me for the next five years and guiding my career development. My immediate goal is to gain practical clinical research experience by conducting a five-year prospective study with this team of experienced and highly respected researchers. My long-term career goals are to help identify spine patient populations more concretely, measure end-results of spinal disorders in general, and define outcomes for treated and untreated back pain and whiplash injuries in particular. Research Project: The use of surgery for back pain is rapidly growing; data on its safety and outcomes are sorely needed. We propose a prospective cohort study to measure the frequency of complications in lumbar fusion surgery, variation in rates of specific serious complications with different types of lumbar fusion, clinical and functional consequences for specific types of complications, and patient or treatment characteristics that predict particularly severe complications. Over a two-year interval, we propose to enroll 1000 patients choosing fusion surgery for treatment of disc degeneration, spondylolisthesis, spinal stenosis, and adult degenerative scoliosis. We will follow these patients for two years, measure predictor patient and treatment characteristics, and measure consequences with clinical and functional outcomes. Accumulating data will be stored in an existing central database. The analysis will use appropriate univariate and multivariate techniques to address the study questions. This study will provide data on the relative benefits and risks of lumbar fusion surgery in treating back pain.